His gubernatorial record on the environment has little in common with his positions in the presidential race, those who knew him in Massachusetts say.

WASHINGTON — During his first 18 months as governor of Massachusetts, Mitt Romney spent considerable time hammering out a sweeping climate change plan to reduce the state's greenhouse gas emissions.

As staff briefed him on possible measures and environmentalists pressed him to act, Romney frequently repeated a central thought, people at those meetings said: That climate change is occurring, that the United States has the resources to handle its vast impact but that low-lying poor countries like Bangladesh would suffer greatly.

"It was like a mantra with him," said a person who attended those meetings who declined to be identified because of the sensitivity of the topic. "His Cabinet members would look at him like, 'What?' He was the radical in the room."

Before doing an about-face toward the end of his term as he began to prepare for his first run for president, Romney pushed to close old coal-fired plants, encourage the development of renewable energy and contain sprawl — steps similar to some President Obama has taken.

Indeed, one of Romney's top environmental staffers, Gina McCarthy, now runs the air pollution unit of the Environmental Protection Agency under Obama. John Holdren, a scientist Romney turned to on at least one occasion to discuss climate change, is the White House senior advisor on science and technology issues.

Romney's gubernatorial record on energy and the environment has little in common with the positions he has staked out in the presidential race, those who knew him in Massachusetts say. The presumptive Republican nominee expresses doubts about climate science like the majority of his party, and his official website has no mention of environmental policy, except for reining in the Clean Air Act and the EPA.

The gulf between his past actions and current rhetoric has many, including some Republicans, wondering which positions he would take if he won in November. Would Romney stick to an energy plan heavily tilted to boosting oil and gas development and reducing regulation? Or would he tack back to the moderate positions he once embraced as Massachusetts governor?

Romney's top energy donors are from fossil fuel companies. Oil, coal and natural gas interests are pouring hundreds of millions of dollars into defeating Obama. And the Republican base is not shy about speaking out on global warming or oil drilling.

"He's sort of been all over the map on many of these issues, and clearly there's always a concern that we won't get the market-based energy policies we'd want," said Wayne Brough, chief economist with FreedomWorks, a tea party group. "The way you resolve those concerns about his past is for him to hear our activism, to hear from the tea party, 'This is where we want to go.' "

The Romney campaign says there is no contradiction between what he says on the stump now and what he did as Massachusetts governor, from 2003 through early 2007.

"He's a supporter of renewable energy, as long as it's anything that would be economically competitive. He doesn't know the extent to which climate change is occurring or that human activity is causing it."

Cass added: "What you won't see are mandates or taxes or regulations that interfere with economic activity."

As a presidential candidate at a time when denying climate change and boosting fossil fuels have become articles of faith for most conservatives, Romney says he plans to aid coal and oil production if elected, pare back environmental regulations and place alternative energy on the back burner.

In a March op-ed, he wrote that instead of backing "real energy," Obama pushed renewables such as wind and solar power. Romney has called for amending the Clean Air Act so that the EPA could not regulate greenhouse gas emissions like carbon dioxide — a move his critics say would allow politicians, not scientists, to determine what is a pollutant.

"I exhale carbon dioxide," Romney said in November in New Hampshire. "I don't want those guys following me around with a meter to see if I'm breathing too hard."

The EPA curtailed greenhouse gas emissions as a result of a 2007 Supreme Court suit, Massachusetts vs. EPA, brought by the state's attorney general during Romney's tenure. While Romney played no role in the lawsuit, he wasn't "hostile to it either," said Seth Kaplan, vice president of policy at the Conservation Law Foundation in Boston.

Among the handful of issues Romney focused on as governor, in fact, was climate change. "We probably spent more time discussing climate change than anything else," said Douglas Foy, Romney's former "supersecretary" who oversaw environmental, energy, transportation and housing policy.